]>
Commit | Line | Data |
---|---|---|
edc97986 | 1 | /************************************************************************** |
2 | * Copyright(c) 1998-2003, ALICE Experiment at CERN, All rights reserved. * | |
3 | * * | |
4 | * Author: The ALICE Off-line Project. * | |
5 | * Contributors are mentioned in the code where appropriate. * | |
6 | * * | |
7 | * Permission to use, copy, modify and distribute this software and its * | |
8 | * documentation strictly for non-commercial purposes is hereby granted * | |
9 | * without fee, provided that the above copyright notice appears in all * | |
10 | * copies and that both the copyright notice and this permission notice * | |
11 | * appear in the supporting documentation. The authors make no claims * | |
12 | * about the suitability of this software for any purpose. It is * | |
13 | * provided "as is" without express or implied warranty. * | |
14 | **************************************************************************/ | |
090026bf | 15 | |
16 | /* $Id$ */ | |
17 | ||
edc97986 | 18 | /////////////////////////////////////////////////////////////////// |
19 | // // | |
20 | // A straight line is coded as a point (3 Double_t) and // | |
21 | // 3 direction cosines // | |
22 | // // | |
23 | /////////////////////////////////////////////////////////////////// | |
090026bf | 24 | |
edc97986 | 25 | #include <Riostream.h> |
090026bf | 26 | #include <TMath.h> |
27 | ||
edc97986 | 28 | #include "AliStrLine.h" |
29 | ||
66b0310c | 30 | using std::endl; |
31 | using std::cout; | |
edc97986 | 32 | ClassImp(AliStrLine) |
33 | ||
34 | //________________________________________________________ | |
fe12e09c | 35 | AliStrLine::AliStrLine() : |
36 | TObject(), | |
c48f9ca2 | 37 | fWMatrix(0), |
38 | fTpar(0) | |
fe12e09c | 39 | { |
edc97986 | 40 | // Default constructor |
41 | for(Int_t i=0;i<3;i++) { | |
42 | fP0[i] = 0.; | |
28dc94e2 | 43 | fSigma2P0[i] = 0.; |
edc97986 | 44 | fCd[i] = 0.; |
45 | } | |
4e1be1bf | 46 | SetIdPoints(65535,65535); |
edc97986 | 47 | } |
48 | ||
49 | //________________________________________________________ | |
b26b5f2c | 50 | AliStrLine::AliStrLine(const Double_t *const point, const Double_t *const cd, Bool_t twopoints, UShort_t id1, UShort_t id2) : |
fe12e09c | 51 | TObject(), |
c48f9ca2 | 52 | fWMatrix(0), |
53 | fTpar(0) | |
fe12e09c | 54 | { |
edc97986 | 55 | // Standard constructor |
24a0c65f | 56 | // if twopoints is true: point and cd are the 3D coordinates of |
57 | // two points defininig the straight line | |
58 | // if twopoint is false: point represents the 3D coordinates of a point | |
59 | // belonging to the straight line and cd is the | |
60 | // direction in space | |
b26b5f2c | 61 | for(Int_t i=0;i<3;i++) |
146c29df | 62 | fSigma2P0[i] = 0.; |
24a0c65f | 63 | |
b26b5f2c | 64 | if(twopoints) |
2c9641ee | 65 | InitTwoPoints(point,cd); |
b26b5f2c | 66 | else |
2c9641ee | 67 | InitDirection(point,cd); |
b26b5f2c | 68 | |
4e1be1bf | 69 | SetIdPoints(id1,id2); |
2c9641ee | 70 | } |
24a0c65f | 71 | |
b26b5f2c | 72 | |
28dc94e2 | 73 | //________________________________________________________ |
b26b5f2c | 74 | AliStrLine::AliStrLine(const Double_t *const point, const Double_t *const sig2point, const Double_t *const cd, Bool_t twopoints, UShort_t id1, UShort_t id2) : |
28dc94e2 | 75 | TObject(), |
c48f9ca2 | 76 | fWMatrix(0), |
77 | fTpar(0) | |
28dc94e2 | 78 | { |
79 | // Standard constructor | |
80 | // if twopoints is true: point and cd are the 3D coordinates of | |
81 | // two points defininig the straight line | |
82 | // if twopoint is false: point represents the 3D coordinates of a point | |
83 | // belonging to the straight line and cd is the | |
84 | // direction in space | |
b26b5f2c | 85 | for(Int_t i=0;i<3;i++) |
146c29df | 86 | fSigma2P0[i] = sig2point[i]; |
28dc94e2 | 87 | |
b26b5f2c | 88 | if(twopoints) |
146c29df | 89 | InitTwoPoints(point,cd); |
b26b5f2c | 90 | else |
146c29df | 91 | InitDirection(point,cd); |
b26b5f2c | 92 | |
4e1be1bf | 93 | SetIdPoints(id1,id2); |
146c29df | 94 | } |
b26b5f2c | 95 | |
146c29df | 96 | //________________________________________________________ |
b26b5f2c | 97 | AliStrLine::AliStrLine(const Double_t *const point, const Double_t *const sig2point, const Double_t *const wmat, const Double_t *const cd, Bool_t twopoints, UShort_t id1, UShort_t id2) : |
146c29df | 98 | TObject(), |
c48f9ca2 | 99 | fWMatrix(0), |
100 | fTpar(0) | |
146c29df | 101 | { |
102 | // Standard constructor | |
103 | // if twopoints is true: point and cd are the 3D coordinates of | |
104 | // two points defininig the straight line | |
105 | // if twopoint is false: point represents the 3D coordinates of a point | |
106 | // belonging to the straight line and cd is the | |
107 | // direction in space | |
c48f9ca2 | 108 | Int_t k = 0; |
109 | fWMatrix = new Double_t [6]; | |
146c29df | 110 | for(Int_t i=0;i<3;i++){ |
111 | fSigma2P0[i] = sig2point[i]; | |
c48f9ca2 | 112 | for(Int_t j=0;j<3;j++)if(j>=i)fWMatrix[k++]=wmat[3*i+j]; |
146c29df | 113 | } |
b26b5f2c | 114 | if(twopoints) |
146c29df | 115 | InitTwoPoints(point,cd); |
b26b5f2c | 116 | else |
146c29df | 117 | InitDirection(point,cd); |
146c29df | 118 | |
4e1be1bf | 119 | SetIdPoints(id1,id2); |
28dc94e2 | 120 | } |
c48f9ca2 | 121 | |
122 | //________________________________________________________ | |
4c03f144 | 123 | AliStrLine::AliStrLine(const AliStrLine &source): |
124 | TObject(source), | |
125 | fWMatrix(0), | |
126 | fTpar(source.fTpar) | |
127 | { | |
128 | // | |
c48f9ca2 | 129 | // copy constructor |
4c03f144 | 130 | // |
c48f9ca2 | 131 | for(Int_t i=0;i<3;i++){ |
132 | fP0[i]=source.fP0[i]; | |
133 | fSigma2P0[i]=source.fSigma2P0[i]; | |
134 | fCd[i]=source.fCd[i]; | |
135 | } | |
45e278c6 | 136 | if(source.fWMatrix){ |
137 | fWMatrix = new Double_t [6]; | |
138 | for(Int_t i=0;i<6;i++)fWMatrix[i]=source.fWMatrix[i]; | |
139 | } | |
4e1be1bf | 140 | for(Int_t i=0;i<2;i++) fIdPoint[i]=source.fIdPoint[i]; |
c48f9ca2 | 141 | } |
142 | ||
143 | //________________________________________________________ | |
4c03f144 | 144 | AliStrLine& AliStrLine::operator=(const AliStrLine& source) |
145 | { | |
c48f9ca2 | 146 | // Assignment operator |
147 | if(this !=&source){ | |
d6853b35 | 148 | TObject::operator=(source); |
4c03f144 | 149 | for(Int_t i=0;i<3;i++){ |
150 | fP0[i]=source.fP0[i]; | |
151 | fSigma2P0[i]=source.fSigma2P0[i]; | |
152 | fCd[i]=source.fCd[i]; | |
153 | } | |
154 | ||
155 | delete [] fWMatrix; | |
156 | fWMatrix=0; | |
157 | if(source.fWMatrix){ | |
158 | fWMatrix = new Double_t [6]; | |
159 | for(Int_t i=0;i<6;i++)fWMatrix[i]=source.fWMatrix[i]; | |
160 | } | |
161 | for(Int_t i=0;i<2;i++) fIdPoint[i]=source.fIdPoint[i]; | |
c48f9ca2 | 162 | } |
163 | return *this; | |
164 | } | |
165 | ||
166 | //________________________________________________________ | |
167 | void AliStrLine::GetWMatrix(Double_t *wmat)const { | |
168 | // Getter for weighting matrix, as a [9] dim. array | |
169 | if(!fWMatrix)return; | |
170 | Int_t k = 0; | |
171 | for(Int_t i=0;i<3;i++){ | |
172 | for(Int_t j=0;j<3;j++){ | |
173 | if(j>=i){ | |
174 | wmat[3*i+j]=fWMatrix[k++]; | |
175 | } | |
176 | else{ | |
177 | wmat[3*i+j]=wmat[3*j+i]; | |
178 | } | |
179 | } | |
180 | } | |
181 | } | |
182 | ||
183 | //________________________________________________________ | |
184 | void AliStrLine::SetWMatrix(const Double_t *wmat) { | |
185 | // Setter for weighting matrix, strating from a [9] dim. array | |
186 | if(fWMatrix)delete [] fWMatrix; | |
187 | fWMatrix = new Double_t [6]; | |
188 | Int_t k = 0; | |
189 | for(Int_t i=0;i<3;i++){ | |
190 | for(Int_t j=0;j<3;j++)if(j>=i)fWMatrix[k++]=wmat[3*i+j]; | |
191 | } | |
192 | } | |
193 | ||
24a0c65f | 194 | //________________________________________________________ |
b26b5f2c | 195 | void AliStrLine::InitDirection(const Double_t *const point, const Double_t *const cd) |
196 | { | |
24a0c65f | 197 | // Initialization from a point and a direction |
b26b5f2c | 198 | Double_t norm = cd[0]*cd[0]+cd[1]*cd[1]+cd[2]*cd[2]; |
199 | ||
edc97986 | 200 | if(norm) { |
b26b5f2c | 201 | norm = TMath::Sqrt(1./norm); |
202 | for(Int_t i=0;i<3;++i) { | |
203 | fP0[i]=point[i]; | |
204 | fCd[i]=cd[i]*norm; | |
205 | } | |
206 | fTpar = 0.; | |
edc97986 | 207 | } |
b26b5f2c | 208 | else AliFatal("Null direction cosines!!!"); |
edc97986 | 209 | } |
210 | ||
24a0c65f | 211 | //________________________________________________________ |
b26b5f2c | 212 | void AliStrLine::InitTwoPoints(const Double_t *const pA, const Double_t *const pB) |
213 | { | |
24a0c65f | 214 | // Initialization from the coordinates of two |
215 | // points in the space | |
216 | Double_t cd[3]; | |
217 | for(Int_t i=0;i<3;i++)cd[i] = pB[i]-pA[i]; | |
218 | InitDirection(pA,cd); | |
219 | } | |
220 | ||
edc97986 | 221 | //________________________________________________________ |
222 | AliStrLine::~AliStrLine() { | |
223 | // destructor | |
c48f9ca2 | 224 | if(fWMatrix)delete [] fWMatrix; |
edc97986 | 225 | } |
226 | ||
227 | //________________________________________________________ | |
228 | void AliStrLine::PrintStatus() const { | |
229 | // Print current status | |
230 | cout <<"=======================================================\n"; | |
231 | cout <<"Direction cosines: "; | |
232 | for(Int_t i=0;i<3;i++)cout <<fCd[i]<<"; "; | |
233 | cout <<endl; | |
234 | cout <<"Known point: "; | |
235 | for(Int_t i=0;i<3;i++)cout <<fP0[i]<<"; "; | |
236 | cout <<endl; | |
28dc94e2 | 237 | cout <<"Error on known point: "; |
238 | for(Int_t i=0;i<3;i++)cout <<TMath::Sqrt(fSigma2P0[i])<<"; "; | |
239 | cout <<endl; | |
edc97986 | 240 | cout <<"Current value for the parameter: "<<fTpar<<endl; |
edc97986 | 241 | } |
242 | ||
243 | //________________________________________________________ | |
b26b5f2c | 244 | Int_t AliStrLine::IsParallelTo(const AliStrLine *line) const { |
edc97986 | 245 | // returns 1 if lines are parallel, 0 if not paralel |
9e224d91 | 246 | const Double_t prec=1e-14; |
edc97986 | 247 | Double_t cd2[3]; |
248 | line->GetCd(cd2); | |
b26b5f2c | 249 | |
edc97986 | 250 | Double_t vecpx=fCd[1]*cd2[2]-fCd[2]*cd2[1]; |
b26b5f2c | 251 | Double_t mod=TMath::Abs(fCd[1]*cd2[2])+TMath::Abs(fCd[2]*cd2[1]); |
252 | if(TMath::Abs(vecpx) > prec*mod) return 0; | |
253 | ||
edc97986 | 254 | Double_t vecpy=-fCd[0]*cd2[2]+fCd[2]*cd2[0]; |
b26b5f2c | 255 | mod=TMath::Abs(fCd[0]*cd2[2])+TMath::Abs(fCd[2]*cd2[0]); |
256 | if(TMath::Abs(vecpy) > prec*mod) return 0; | |
257 | ||
edc97986 | 258 | Double_t vecpz=fCd[0]*cd2[1]-fCd[1]*cd2[0]; |
b26b5f2c | 259 | mod=TMath::Abs(fCd[0]*cd2[1])+TMath::Abs(fCd[1]*cd2[0]); |
9e224d91 | 260 | if(TMath::Abs(vecpz) > prec) return 0; |
b26b5f2c | 261 | |
edc97986 | 262 | return 1; |
263 | } | |
264 | //________________________________________________________ | |
b26b5f2c | 265 | Int_t AliStrLine::Crossrphi(const AliStrLine *line) |
266 | { | |
edc97986 | 267 | // Cross 2 lines in the X-Y plane |
9e224d91 | 268 | const Double_t prec=1e-14; |
269 | const Double_t big=1e20; | |
edc97986 | 270 | Double_t p2[3]; |
271 | Double_t cd2[3]; | |
272 | line->GetP0(p2); | |
273 | line->GetCd(cd2); | |
274 | Double_t a=fCd[0]; | |
275 | Double_t b=-cd2[0]; | |
276 | Double_t c=p2[0]-fP0[0]; | |
277 | Double_t d=fCd[1]; | |
278 | Double_t e=-cd2[1]; | |
279 | Double_t f=p2[1]-fP0[1]; | |
280 | Double_t deno = a*e-b*d; | |
b26b5f2c | 281 | Double_t mod=TMath::Abs(a*e)+TMath::Abs(b*d); |
edc97986 | 282 | Int_t retcode = 0; |
b26b5f2c | 283 | if(TMath::Abs(deno) > prec*mod) { |
edc97986 | 284 | fTpar = (c*e-b*f)/deno; |
285 | } | |
286 | else { | |
9e224d91 | 287 | fTpar = big; |
edc97986 | 288 | retcode = -1; |
289 | } | |
290 | return retcode; | |
291 | } | |
292 | ||
293 | //________________________________________________________ | |
294 | Int_t AliStrLine::CrossPoints(AliStrLine *line, Double_t *point1, Double_t *point2){ | |
295 | // Looks for the crossing point estimated starting from the | |
296 | // DCA segment | |
9e224d91 | 297 | const Double_t prec=1e-14; |
edc97986 | 298 | Double_t p2[3]; |
299 | Double_t cd2[3]; | |
300 | line->GetP0(p2); | |
301 | line->GetCd(cd2); | |
302 | Int_t i; | |
303 | Double_t k1 = 0; | |
edc97986 | 304 | Double_t k2 = 0; |
edc97986 | 305 | Double_t a11 = 0; |
c48f9ca2 | 306 | for(i=0;i<3;i++){ |
307 | k1+=(fP0[i]-p2[i])*fCd[i]; | |
308 | k2+=(fP0[i]-p2[i])*cd2[i]; | |
309 | a11+=fCd[i]*cd2[i]; | |
310 | } | |
edc97986 | 311 | Double_t a22 = -a11; |
312 | Double_t a21 = 0; | |
edc97986 | 313 | Double_t a12 = 0; |
c48f9ca2 | 314 | for(i=0;i<3;i++){ |
315 | a21+=cd2[i]*cd2[i]; | |
316 | a12-=fCd[i]*fCd[i]; | |
317 | } | |
edc97986 | 318 | Double_t deno = a11*a22-a21*a12; |
b26b5f2c | 319 | Double_t mod = TMath::Abs(a11*a22)+TMath::Abs(a21*a12); |
320 | if(TMath::Abs(deno) < prec*mod) return -1; | |
edc97986 | 321 | fTpar = (a11*k2-a21*k1) / deno; |
322 | Double_t par2 = (k1*a22-k2*a12) / deno; | |
323 | line->SetPar(par2); | |
324 | GetCurrentPoint(point1); | |
325 | line->GetCurrentPoint(point2); | |
326 | return 0; | |
327 | } | |
328 | //________________________________________________________________ | |
b26b5f2c | 329 | Int_t AliStrLine::Cross(AliStrLine *line, Double_t *point) |
330 | { | |
edc97986 | 331 | |
332 | //Finds intersection between lines | |
333 | Double_t point1[3]; | |
334 | Double_t point2[3]; | |
335 | Int_t retcod=CrossPoints(line,point1,point2); | |
336 | if(retcod==0){ | |
337 | for(Int_t i=0;i<3;i++)point[i]=(point1[i]+point2[i])/2.; | |
338 | return 0; | |
339 | }else{ | |
340 | return -1; | |
341 | } | |
342 | } | |
343 | ||
344 | //___________________________________________________________ | |
b26b5f2c | 345 | Double_t AliStrLine::GetDCA(const AliStrLine *line) const |
346 | { | |
edc97986 | 347 | //Returns the distance of closest approach between two lines |
9e224d91 | 348 | const Double_t prec=1e-14; |
edc97986 | 349 | Double_t p2[3]; |
350 | Double_t cd2[3]; | |
351 | line->GetP0(p2); | |
352 | line->GetCd(cd2); | |
353 | Int_t i; | |
354 | Int_t ispar=IsParallelTo(line); | |
355 | if(ispar){ | |
356 | Double_t dist1q=0,dist2=0,mod=0; | |
357 | for(i=0;i<3;i++){ | |
358 | dist1q+=(fP0[i]-p2[i])*(fP0[i]-p2[i]); | |
359 | dist2+=(fP0[i]-p2[i])*fCd[i]; | |
360 | mod+=fCd[i]*fCd[i]; | |
361 | } | |
9e224d91 | 362 | if(TMath::Abs(mod) > prec){ |
edc97986 | 363 | dist2/=mod; |
364 | return TMath::Sqrt(dist1q-dist2*dist2); | |
365 | }else{return -1;} | |
366 | }else{ | |
367 | Double_t perp[3]; | |
368 | perp[0]=fCd[1]*cd2[2]-fCd[2]*cd2[1]; | |
369 | perp[1]=-fCd[0]*cd2[2]+fCd[2]*cd2[0]; | |
370 | perp[2]=fCd[0]*cd2[1]-fCd[1]*cd2[0]; | |
371 | Double_t mod=0,dist=0; | |
372 | for(i=0;i<3;i++){ | |
373 | mod+=perp[i]*perp[i]; | |
374 | dist+=(fP0[i]-p2[i])*perp[i]; | |
375 | } | |
b26b5f2c | 376 | if(TMath::Abs(mod) > prec) { |
377 | return TMath::Abs(dist/TMath::Sqrt(mod)); | |
378 | } else return -1; | |
edc97986 | 379 | } |
380 | } | |
381 | //________________________________________________________ | |
382 | void AliStrLine::GetCurrentPoint(Double_t *point) const { | |
383 | // Fills the array point with the current value on the line | |
384 | for(Int_t i=0;i<3;i++)point[i]=fP0[i]+fCd[i]*fTpar; | |
385 | } | |
2c9641ee | 386 | |
387 | //________________________________________________________ | |
b26b5f2c | 388 | Double_t AliStrLine::GetDistFromPoint(const Double_t *point) const |
389 | { | |
2c9641ee | 390 | // computes distance from point |
b26b5f2c | 391 | AliStrLine tmpline(point, fCd, kFALSE); |
392 | return GetDCA(&tmpline); | |
2c9641ee | 393 | } |
46aed644 | 394 | |
395 | //________________________________________________________ | |
396 | Bool_t AliStrLine::GetParamAtRadius(Double_t r,Double_t &t1,Double_t &t2) const | |
397 | { | |
398 | // Input: radial distance from the origin (x=0, x=0) in the bending plane | |
399 | // Returns a boolean: kTRUE if the line crosses the cylinder of radius r | |
400 | // and axis coincident with the z axis. It returns kFALSE otherwise | |
401 | // Output: t1 and t2 in ascending order. The parameters of the line at | |
402 | // the two intersections with the cylinder | |
403 | Double_t p1= fCd[0]*fP0[0]+fCd[1]*fP0[1]; | |
404 | Double_t p2=fCd[0]*fCd[0]+fCd[1]*fCd[1]; | |
405 | Double_t delta=p1*p1-p2*(fP0[0]*fP0[0]+fP0[1]*fP0[1]-r*r); | |
406 | if(delta<0.){ | |
407 | t1=-1000.; | |
408 | t2=t1; | |
409 | return kFALSE; | |
410 | } | |
411 | delta=TMath::Sqrt(delta); | |
412 | t1=(-p1-delta)/p2; | |
413 | t2=(-p1+delta)/p2; | |
414 | ||
415 | if(t2<t1){ | |
416 | // use delta as a temporary buffer | |
417 | delta=t1; | |
418 | t1=t2; | |
419 | t2=delta; | |
420 | } | |
421 | if(TMath::AreEqualAbs(t1,t2,1.e-9))t1=t2; | |
422 | return kTRUE; | |
423 | } |